Pole clamp



Jan. 16, 1934.

J. J. M DONALD POLE CLAMP Filed Sept. 30, 1929 Patented Jan. 16, 1934UNETD STATES PATENT OFFICE assignor to Frank M. Simpson,

Canada Montreal,

Application September 30, 1929 Serial No. 396,224

7 Claims. (01. 189--33) This invention relates to improvements in crossarm supports and the object of the invention is to provide a supportquickly and easily adjustable to the size or" the pole to which it is tobe applied and adaptable to cross arms of different sizes and crosssections. A further object is to provide a cross arm support which willobviate the use of the usual braces and will hold a cross arm rigidly inrelation to a pole. A still further object is to provide a cross armsupport which may be attached to a pole without checking into the poleor boring bolt holes therein. Another object is to provide a cross armsupport which may, if desired, be attached to a pole by means of asingle bolt and which will hold a cross arm rigidly to the pole withoutthe use of braces. Various other objects and the advantages of theinvention may be ascertained from the following description and theaccompanying drawing.

Briefly, the device comprises a pair of similar rectangular platesrelatively adjustable in their longitudinal direction, each of saidplates having on one side flanges curved on their edges to engage a poleand on the other side lugs or flanges to snugly embrace a cross arm. Theplates are provided with registering apertures for passage of fasteningmeans to secure them in proper adjustment and to a pole and cross arm.

. In the accompanying drawing which illustrates an acceptable form ofthe invention, but to the details of which the invention is notconfined, as numerous modifications are possible;-

Fig. l is a plan view of one form of support in position on a pole.

Fig. 2 is an end elevation of the support.

Fig. 3 is an elevation of the pole side of the device.

Figs. 4 and 5 are elevations of the. plates separated and illustratingtheir relation to each other.

Referring more particularly to the drawing, 11 and 12 designate a pairof similar oblong plates, the width of which is approximately equal tothe 4 depth of a cross arm with which the device is to be used. Each ofthe plates is provided toward one end and on its long edges withapproximately triangular opposite flanges l3 projecting from the frontface of the plate, i. e., the face which will be next to a pole, and atapproximately right angles to the plane of the plate. The inner edges l-i of these flanges, that is, the edges re mote from the plate endsdiverge and may be concavely curved, the curvature preferablycorrespondingsubstantially to the surface curvature of the smallest polefor which the device is adapted. It will be understood, however, thatthe shape of the flanges, their angular relation to the plates and theexact edge curvature are not material and may be varied as desired, andthat the flanges may be integral with the plates or separately formedand subsequently attached. Each plate is provided on its long edges ateach end with opposite lugs or flanges 15 projecting from the rear faceof the plate, preferably in slightly divergent relation to facilitateapplication to and ensure tight grip on a cross arm, but the lugs on theupper edges may be omitted.

Diagonally opposite corners of the plates are provided with apertures 16arranged in series and so disposed that when the plates are superposedthe apertures will register in a great many different adjustments andpermit the passage of fastenings therethrough to hold the plates in thedesired adjustment. These apertures are preferably slots arrangedangularly at a slight inclination to the transverse direction of theplates, the inclination or pitch being preferably half the spacing ofthe slots. Also, the slots at opposite ends of the plates are oppositelyinclined so that when the plates are superposed the slots of one platewill cross the slots of the other plate and enable the plates to befastened in an infinite variety of adjustments.

Each plate is provided along its central longitudinal line with a seriesof longitudinally extending slots l7, l8 and 19, correspondinglynumbered slots of the two plates being formed and disposed to registerin whatever adjustment the plates are set to provide a central openingand two elongated openings at opposite ends thereof in every adjustmentof the plates, as clearly shown in Figure 3. As will be seen bycomparison of Figures 4 and 5, the slot 19 of each plate registers withthe slot 1'? of the other plate and the two slots is register with eachother.

It will be seen that the plates 11 and 12 are exactly alike and may bestamped out of sheet metal with a single die and that, when assembled,one between the flanges of .the other, the plates may be relativelyadjusted in their longitudinal direction but are held in alignment bythe flanges and lugs. The limits of adjustment are determined byengagement of the lugs and flanges of one plate with those of the otherplate. A greater range of adjustment may be obtained by omitting thelugs from the plate nearest the pole or, conversely, the same range ofadjustment may be obtained with shorter plates if the plate next thepole is formed without lugs.

The support is applied as followsz--two plates are assembled insuperposed relation, so that the curved edges 14 of the flanges 13 ofthe two plates are facing, as clearly shown in Figure 1. If one of theplates should be without lugs 15, it is placed below the lug bearingplate and the two plates are then placed on a cross arm, designated 20,which will then be embraced between the lugs of the outermost plate 11.If lugs are provided on only one edge, these lugs will be placed againstthe bottom of the cross arm. The plates are adjusted longitudinallyuntil their flanges 13 are of such distance apart that their curvededges Will bite slightly into the curved surface of a pole when appliedthereto,

cross arm and support are now ready for attachment to a pole either bymeans of a single through bolt (not shown) or by means of a U- bolt 23.If a through bolt is used, it will pass through the pole through theapertures 18 of the plates and through the cross arm and, when the nutis tightened, will draw the cross arm toward the pole, so that thecurved edges of the support flanges 13, which constitute pole embracingjaws, will bite into the pole sufficiently to hold the cross arm andsupport against rocking and at the same time resist splitting of thepole. The preferable method. of attachment is by means of a U -boltwhich passes around the pole and through the registering apertures 17and 19 of the plates and through the cross arm. When the nuts of thisbolt are tightened up, they draw the cross arm and support toward thepole, so that the edges of the flanges 13 will bite into the pole andhold the cross arm and support against rocking. The U-bolt is preferableto a through bolt, since it does not weaken the pole or necessitate anopening which invites rotting of the pole but, on the contrary, resistssplitting of the pole. The U-bolt is further preferable because thedouble support which it affords adds to the stability of the structureand enables the cross arm to be ad' justed around the pole. The bitingof the flanges 13 into the poles is obviously crosswise of the grain, sothat there is no possibility of the support slipping down on the poleeven when a U-bolt is used and, if the nuts are properly tightened, theengagement is sufficiently tight, so that there is no possibility of thecross arm twisting around the pole. Furthermore, the engagement issubstantially at opposite sides of the pole so that great stability isensured. While the central part of the U-bolt where it encircles thepole may be either round or flat, it is preferred to make the same ofchannel section, as indicated in Figures 3. and 2, so that the bolt aswell as the flanges 13 of the support will bite into the pole and thusincrease the grip. The lugs 15 of the plates embrace the cross arm at aconsiderable distance on each side of the pole and hold the same againstrocking in a vertical plane. If only one of the plates is provided withlugs, the effect is the same. Owing to the fact that the lugs 15 snuglyembrace the cross arm that the and flanges of the plates engage theedges of the plates and hold them rigidly in alignment with. one anotherand with the cross arm, it will be evident that the support is rigidlyheld to the cross arm against rocking, i. e., relative movement in avertical plane. The engagement of the flanges with the pole has beenfound so much more effective than the old method of checking the crossarm into the pole that the usual angle braces are unnecessary.

If the curved edges of the flanges are suitably designed, a single sizeof support will serve for all sizes of poles in general use, but it isobvious that, if desired, the device may be made in a variety of sizesaccording to the sizes of poles on which it is to be used. Using thissupport, cross arms may be attached to poles more easily and morequickly than is generally the case, particularly when a U-bolt is used.

Having thus described my invention, what I claim is l. A cross armsupport comprising a pair of plates, flanges on said plates adapted toengage edgewise with a pole, one of said plates being embraced betweenthe flanges of the other plate, and lugs on said embraced plateembracing the other plate and adapted to embrace a cross arm, and meansto clamp the plates between a pole and a cross arm.

2. A cross arm support comprising a pair of oblong superposed platesrelatively adjustable in their longitudinal direction, flanges on saidplates adapted to engage edgewise with a pole, lugs on said platesadapted to engage a cross arm, each of said plates being formed with aseries of inclined slots, the slots of one plate inclining oppositely tothe slots of the other plate in the superposed relation of the plates,whereby the slots of the two plates will be in register in anyadjustment of the plates, fastening means engaged in said slots securingthe plates in an adjustment which spaces the flanges thereof suitably tothe size of pole to which they are to be applied, and means for clampingthe plates between a pole and a cross arm.

3. A cross arm support compri ing a pair of oblong superposed platesrelatively adjustable in their longitudinal direction, flanges on saidplates adapted to engage edgewise with a pole, lugs on said platesadapted to engage a cross arm, each of said plates being formed atdiagonally opposite corners with a series of inclined slots, the slotsin one corner being oppositely inclined to the slots of the diagonallyopposite corner whereby the slots of one plate are oppositely inclinedto the slots of the other plate with which they register, fasteningmeans engaged in said slots securing the plates in an adjustment whichspaces the flanges thereof suitably to the size of pole to which theyare to be applied, and means for clamping the plates between a pole anda cross arm.

4. A cross arm support element including an oblong body; a plurality ofelongated slots in said oblong body along the central longitudinal linethereof; a pair of transversely opposed pole contact flanges on the longedges of said oblong body towards one end thereof; and a pair of crossarm contact lugs at each end of said body extending from the long edgesthereof in transversely opposed relation.

5. A cross arm support element including an oblong body; a plurality ofelongated slots in said oblong body along the central longitudinal lineth reof; a plurality of slots in diagonally opposite corners of saidoblong body; a pair of transversely opposed pole contact flanges on the7 long edges of said oblong body towards one end thereof; and a pair ofcross arm contact lugs at each end of said body extending from the longedges thereof in transversely opposed relation.

6. A cross arm support element including an oblong body; a plurality ofelongated slots in said oblong body along the central longitudinal linethereof; a plurality of slots in corners of' 7. A cross arm supportelement in the form of a pressed metal oblong body having transverselyopposed pole contact flanges extending from the long edges of saidoblong body in close proximity to one end thereof; cross arm engaginglugs extending from the long edges of said oblong body in opposedrelation from the ends of said oblong body and in the opposite directionto the aforesaid flanges; a plurality of elongated slots in said oblongbody extending along the central longitudinal line thereof; and aplurality of slots in corners of said oblong body inclined with respectto said elongated slots.

JOHN J. MACDONALD.

